# CVE-2026-12219: Yealink SIP-T46U Web FastCGI Service start mod_diagnose.CommandShellByType command injection

> Remote attackers can execute arbitrary commands on Yealink SIP-T46U phones via the Web FastCGI service, requiring a firmware upgrade.

- **Severity:** Medium 5.3 (`CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Jun 2026
- **Updated:** 27 Jun 2026
- **Also known as:** GHSA-85r6-756v-4x2v

## What is CVE-2026-12219?

CVE-2026-12219 is a medium-severity command injection vulnerability in Yealink SIP-T46U, published on 15 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

A flaw has been found in Yealink SIP-T46U 108.86.0.118. The impacted element is the function mod_diagnose.CommandShellByType of the file /api/diagnosis/start of the component Web FastCGI Service. This manipulation of the argument Time causes command injection. The attack can be initiated remotely. The exploit has been published and may be used. Upgrading to version 108.87.0.23 is sufficient to resolve this issue. It is advisable to upgrade the affected component.

Weakness: CWE-77 (Improper Neutralization of Special Elements used in a Command), CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component)

## Which versions are affected by CVE-2026-12219?


## How do I fix CVE-2026-12219?

No fix has been published for CVE-2026-12219 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-12219 being exploited?

There is no known exploitation of CVE-2026-12219 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-12219 and fix it if it is affected.

What it is: CVE-2026-12219 is a medium-severity command injection vulnerability in Yealink SIP-T46U, published on 15 Jun 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-12219 in the wild and no public exploit code.

Affected product: Yealink SIP-T46U. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-12219/ (Markdown: https://insights.sbomify.com/CVE-2026-12219/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-12219
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-12219
- OSV: https://osv.dev/vulnerability/CVE-2026-12219

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-12219/
Summaries are generated and may contain mistakes; the official description above is the record.